Conventional systems for providing a suspended ceiling generally comprise a plurality of main runners arranged parallel to each other and a plurality of cross runners arranged parallel to each other and perpendicular to the main runners to provide a grid pattern of square open apertures. Both the main runner and cross runners are of an inverted tee cross-section such that the horizontal portion of the runners are able to support a ceiling tile about its periphery. At least the main runners are secured a fixed distance below the bottom of floor joists by hangers which extend between the joists and the vertical portions of the runners.
To install ceiling tiles in such a system, the tiles are tilted, inserted upwardly through one of the apertures in the grid, and then adjusted to the horizontal plane and allowed to drop into place between the main runners and cross runners. This procedure must be reversed to remove tiles for replacement or repair. As a consequence, the grid runners must be spaced beneath the joists a sufficient distance, e.g., at least three inches, to allow for the insertion and removal of the ceiling tiles. For rooms such as basement or attic rooms where headroom is typically quite limited, the installation of a conventional suspended ceiling system even further reduces the headroom, often to an unacceptable level.